Eyeglasses are widely used both to protect the eyes, and to improve vision. The present invention is concerned primarily with safety glasses for protecting the eyes, but the principles are equally applicable to prescription corrective lenses, and also to sunglasses.
Prior art eyeglasses are generally one of two types. One type has lenses supported by a frame with the lenses positioned forwardly of the eyes. These are disadvantageous in that there is pressure on the bridge of the nose, and tension behind the ears from the temple pieces. The second type of prior art eyeglasses comprises contact lenses which are worn directly on the eye in front of the eye lens, and at least in part in contact with the cornea. Many people cannot tolerate contact lenses, and they are available only on prescription. Furthermore, they are of limited use in protecting the eye, and could not generally be classified as safety glasses.
Safety glasses in the past have thus been restricted to lenses mounted in frame and carried in front of the face. These do generally provide satisfactory protection for the eyes, but as indicated may be physically uncomfortable. Futhermore, since they project forwardly of the face, they are in a position where they can be contacted readily by work pieces or the like, thereby being pushed against the nose of the wearer and possibly causing damage thereto, and also bending the frames. There are certain uses of protective glasses, such as working under automobiles, for example, where there is very little room for eye lenses and frames that project forwardly of the face.